_Specimens of the Bridges, Viaducts, &c., on the United Slates Railroads_, by GEORGE DUGGIN, deserves an honorable place by the side of the two preceding serials, as an important contribution to the science of civil engineering in this country. The sixth number has already made its appearance, being the commencement of an elaborate treatise on Bridge-building, illustrated with sketches of the most remarkable specimens in this branch of architecture. The multiplicity of works like those we have just alluded to, and the great and instant popularity which they attain, present a cheering proof of the prevalence of scientific curiosity, and of the mental activity which leads to thorough investigation, among the leading artisans of the United States. _The Second Book in Greek_, by John M'CLINTOCK, published by Harper and Brothers, is the complement to the previous volume, entitled _First Book in Greek_, which, as a practical manual in this branch of philology, has elicited the warmest approbation of judicious teachers. Dr. M'Clintock has brought the resources of a ripe and generous scholarship to the preparation of this work, which, with the other volumes of his Elementary Series in Greek and Latin, is a highly honorable proof of his sound learning and correct taste. The present work gives a full view of the Greek Syntax, with copious illustrations, and extracts from Xenophon's Anabasis, Homer, Anacreon, and sentences from the Greek Dramatists. Its peculiar merit consists in the progressive manner in which the various difficulties of Greek combination are unfolded, the pupil being thus led forward, by a natural sequence, to a mastery of the complicated idioms of the language, and trained imperceptibly to a perception of its rich and wonderful beauties. Lea and Blanchard, Philadelphia, have republished _Impressions and Experiences of the West Indies and North America in 1849_, by ROBERT BAIRD, an intelligent Scotchman, apparently of the legal profession, but with little of the talent essential to the composition of a popular book of travels. His remarks on the United States are in a more discriminating tone than is often attained by English tourists, but the whole tone of the volume is, for the most part, so prosy and commonplace as to make its perusal an intolerable bore.